title: Structural properties and superconductivity of SrFe(2)As(2 - x)P(x) (0.0 ≤ x ≤ 1.0) and CaFe(2)As(2 - y)P(y) (0.0 ≤ y ≤ 0.3).
abstract: The SrFe(2)As(2 - x)P(x) (0.0 ≤ x ≤ 1.0) and CaFe(2)As(2 - y)P(y) (0.0 ≤ y ≤ 0.3) materials were prepared by a solid-state reaction method. X-ray diffraction measurements indicate that the single-phase samples can be successfully obtained for SrFe(2)As(2 - x)P(x) (0.0 ≤ x ≤ 0.8) and CaFe(2)As(2 - y)P(y) (0.0 ≤ y ≤ 0.3). Visible contraction of the lattice parameters is determined due to the relatively smaller radius of P ions in comparison with that of As. The spin-density-wave (SDW) instability associated with the tetragonal to orthorhombic phase transition is suppressed noticeably in both systems following the increase in P content. The highest superconducting transitions are observed at about 27 K in SrFe(2)As(1.3)P(0.7) and at about 13 K in CaFe(2)As(1.925)P(0.075), respectively. Structural analysis suggests that lattice contraction could notably affect the superconductivity in these materials.
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
authors.forename: H L
authors.initials: HL
authors.lastname: Shi
authors.forename: H X
authors.initials: HX
authors.lastname: Yang
authors.forename: H F
authors.initials: HF
authors.lastname: Tian
authors.forename: J B
authors.initials: JB
authors.lastname: Lu
authors.forename: Z W
authors.initials: ZW
authors.lastname: Wang
authors.forename: Y B
authors.initials: YB
authors.lastname: Qin
authors.forename: Y J
authors.initials: YJ
authors.lastname: Song
authors.forename: J Q
authors.initials: JQ
authors.lastname: Li